JP4561893B2 - Data transmitting apparatus, data receiving apparatus, data transmitting method and data receiving method - Google Patents

Description

  The present invention relates to a data transmission device, a data reception device, a data transmission method, and a data reception method, and more particularly to a data transmission device, a data reception device, a data transmission method, and a data reception method for verifying the validity of a device in wireless communication.

Conventionally, for the purpose of protecting copyright of music content, video content, etc., for example, HDMI (High-Definition)
Various protocols such as Multimedia Interface) have been proposed. As a content protection method, for example, HDCP (High-bandwidth Digital)
Content Protection system) is used. In the HDCP standard, device authentication on the transmission side and reception side, a key sharing method for authentication, an encryption method for transmitted content, and the like are defined.

  In authentication such as the HDCP standard, a device key for individually authenticating a communication partner apparatus by public key cryptography is used. When the authentication is successful between the transmission device and the reception device, the transmission device encrypts and transmits the video signal using the device key, and the reception device decrypts the received video signal using the device key.

  In the HDCP standard, the above authentication process is performed, and a so-called Revocation process (hereinafter referred to as a revocation process) for determining whether the receiving apparatus is an unauthorized device is performed. Only after the revocation process determines that the receiving apparatus is not an unauthorized device, encrypted transmission is possible.

  Incidentally, even in the case of a device that wirelessly transmits an image signal, a source device (hereinafter referred to as a source device) such as a recording / playback device, a wireless device (data transmission device), a wireless device (data reception device), a display, and the like. If the sink devices (hereinafter referred to as “sink devices”) are securely connected using HDMI or the like, are the devices mutually authorized using the security information stored in each device? Can be determined. Thereby, it becomes possible to permit signal transmission between different transmission / reception devices.

JP 2003-37591 A JP 2006-128963 A

However, for example, if the data receiving device is embedded in a display or the like and security information such as HDCP is not stored on the receiving side, the content cannot be copied from an unauthorized copy unless it is used with a specific data transmitting device. There was a problem that it could not be protected and was not easy to use.
In wireless communication, image data is compressed according to an image signal by a method using DCT / Wavelet conversion or the like, and image data is transmitted at a reduced transfer rate. For this reason, when content data is encrypted by HDCP, the content data must be encrypted again in order to transmit the image data by wireless communication after the content data is decrypted, resulting in a complicated process. It was.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is a new and improved device capable of performing encryption by wireless communication and verifying the validity of a device. Another object of the present invention is to provide a data transmission device, a data reception device, a data transmission method, and a data reception method.

  In order to solve the above-described problem, according to one aspect of the present invention, a first encryption unit that encrypts image information of input content by a first encryption method and a first encryption unit A wireless communication unit for transmitting the received image information by wireless communication, a second encryption unit for encrypting the image information of the input content by the second encryption method, and the image information encrypted by the second encryption unit A wired communication unit that transmits information by wired communication, a device information acquisition unit that acquires information on connected devices, and a verification that verifies the validity of the data reception device based on the device information acquired by the device information acquisition unit First, when it is verified that the data receiving device is valid by the verification unit, whether the device information is acquired via the wireless communication unit or the device information is acquired via the wired communication unit. By the encryption department A data transmission device comprising: a control unit configured to control whether the image information encrypted by the wireless communication unit is transmitted by the wireless communication unit or the image information encrypted by the second encryption unit is transmitted by the wired communication unit. Provided.

  According to such a configuration, when connecting to the data receiving device by wireless communication, device information of the data receiving device is acquired via the wireless communication unit, and it is verified that the data receiving device is valid. The image information encrypted by the first encryption unit is transmitted by the wireless communication unit. Also, when connecting to the data receiving device by wired communication, the device information of the data receiving device is acquired via the wired communication unit, and when it is verified that the data receiving device is valid, the second encryption unit The wired communication unit transmits the image information encrypted by.

  Thereby, when transmitting the image information of content in wireless communication, it can be encrypted by the first encryption method normally used in wireless communication. In addition, the validity of device information can be verified also in wireless communication. Even when wireless communication is performed, the validity of the data receiving device can be authenticated by using the security information of the wired input, so even if HDCP security information is not stored on the receiving side, other than the specific transmitting device Content data can be transmitted / received to / from other devices while protecting the copyright.

  The control unit may verify the validity of the data receiving device by the verification unit and encrypt the image information by the first encryption unit when connected to the data receiving device by wireless communication. In addition, the device information acquisition unit acquires information on the unauthorized device from the external device, and the verification unit receives the device information on the data reception device in the information on the unauthorized device acquired by the device information acquisition unit. The data receiving device may be determined to be a legitimate device.

  Further, the first encryption unit may compress the image information according to the image information of the content and then encrypt the image information using the first encryption method. The second encryption unit may perform TMDS conversion on the encrypted content image information after encrypting the content image information using the second encryption method.

  The wired communication unit may transmit content image information using a TMDS circuit. Further, the verification unit may verify the data receiving device based on the HDCP standard.

  In order to solve the above problem, according to another aspect of the present invention, a wireless communication unit that receives image information of content by wireless communication from a connected data transmission device, and image information of the received content A first decoding unit that decodes the image data by the first decoding method, a wired communication unit that receives image information of the content from the connected data transmission device by wired communication, and a second image information of the received content A second decoding unit that performs decoding by the decoding method, a device information acquisition unit that acquires connected device information, and the validity of the connected device based on the device information acquired by the device information acquisition unit. The verification unit that verifies the device and whether the device information is acquired via the wireless communication unit or whether the device information is acquired via the wired communication unit, whether the device connected by the verification unit is valid If it is verified, the image information is received by the wireless communication unit and the image information is decoded by the first decoding unit or the image information is received by the wired communication unit and the image information is decoded by the second decoding unit. And a control unit that controls whether or not to enable the data reception.

  According to this configuration, when connecting to the data transmission device by wireless communication, the image information of the content is received from the data transmission device via the wireless communication unit, and the device information of the device connected by wireless communication is acquired. Then, when it is verified that the connected device is valid, the image information encrypted by the first encryption unit is transmitted by the wireless communication unit. In addition, when receiving image information of content from a data transmission device by wired communication, the device information of the data receiving device is acquired via a wired communication unit, and it is verified that the connected device is valid. In this case, the image information encrypted by the second encryption unit is transmitted by the wired communication unit.

  Thereby, when transmitting / receiving content image information in wireless communication, the content image information can be received by wireless communication and encrypted using the first encryption method normally used in wireless communication. In addition, the validity of device information can be verified also in wireless communication. Even when wireless communication is performed, the security information provided for wired input can be used to authenticate the connected device, so wireless HDCP security information is stored on the receiving side. Even if not, content data can be transmitted / received while protecting the copyright with a device other than the specific transmission device. For example, when image data of content is transmitted from a data receiving device to a sink device such as a display by wireless communication, it is possible to verify the validity of the sink device using wired input security information such as a display. Become.

  The control unit may verify the validity of the device by the verification unit and encrypt the image information by the first encryption unit when connected to the device by wireless communication. The device information acquisition unit acquires information on unauthorized devices from an external device, and the verification unit does not include information on connected devices in the information on unauthorized devices acquired by the device information acquisition unit. In addition, the connected device may be determined to be a valid device.

  Further, the first encryption unit may compress the image information according to the image information of the content and then encrypt the image information using the first encryption method. The second encryption unit may perform TMDS conversion on the encrypted content image information after encrypting the content image information using the second encryption method.

  Further, the wired communication unit may receive the image information of the content by the TMDS circuit. Further, the verification unit may verify the connected device based on the HDCP standard.

  In order to solve the above-described problem, according to another aspect of the present invention, a wireless communication unit that receives image information of a content by wireless communication with a connected data transmission device, and first image information of the received content A first decoding unit for decoding by the decoding method, a wired communication unit for receiving image information of the content by wired communication with the connected data transmission device, and the image information of the received content by the second decoding method. A second decoding unit for decoding, a device information transmitting unit for transmitting device information of the data receiving device, and a data receiving device verified by the data transmitting device based on the device information transmitted by the device information transmitting unit. Verification result acquisition unit that acquires a verification result of validity, whether to transmit device information via a wireless communication unit or whether to transmit device information via a wired communication unit, verification result When the obtaining unit obtains a verification result that the data receiving device is valid, the wireless communication unit receives the image information and decodes it by the first decoding unit, or the wired communication unit receives the image information and receives the second information. Data comprising: a control unit that controls whether or not to perform decoding by a decoding unit; and a display screen generation unit that generates a display screen including image information decoded by the first decoding unit or the second decoding unit. A receiving device is provided.

  According to such a configuration, when connecting to the data transmission device by wireless communication, when the validity of the data reception device is confirmed by transmitting device information of the data reception device by wireless communication, the wireless communication unit is The image information of the content is received from the data transmission device. Then, the image information of the content is decoded by the first decoding method, and a display screen including the decoded image information is generated. In addition, when connecting to a data transmission device by wired communication, when the device information of the data reception device is transmitted by wired communication and the validity of the data transmission device is confirmed, data transmission is performed via the wired communication unit. Receive image information of content from the device. Then, the image information of the content is decoded by the second decoding method, and a display screen including the decoded image information is generated.

  Thus, when transmitting and receiving content image information in wireless communication, it is possible to receive content image information through wireless communication and decode it using the first decoding method normally used in wireless communication. In addition, even when wireless communication is performed, it is possible to authenticate the connected device using the security information for wired input, so the wireless HDCP security information is not stored on the receiving side. However, content data can be transmitted and received while protecting the copyright with a device other than the specific transmission device. For example, when the data receiving device and the display device are integrated, it is possible to verify the legitimacy of the data receiving device using wired input security information of the display device or the like.

  The display screen generation unit is provided in a display device incorporated in the data reception device, the device information transmission unit transmits device information of the display device, and the verification result acquisition unit is based on the device information of the display device. You may make it acquire the verification result of the validity of a data receiver verified by the data transmitter.

  In addition, the first decoding method may be a decoding method used when transmitting image information of content by wireless communication. The second decoding method may be a decoding method that decodes image information of content transmitted by wired communication according to the HDCP standard.

  The wired communication unit may receive image information of content by a TMDS circuit. The verification result acquisition unit may acquire the verification result of the validity of the data receiving device verified based on the HDCP standard.

In order to solve the above problem, according to another aspect of the present invention, the step of encrypting the image information of the input content by the first encryption method, and the step of encrypting the image information of the input content by the second The step of encrypting with the encryption method of the above, and obtaining the device information of the connected device via the wireless communication unit that receives the image information of the content by wireless communication, or receiving the image information of the content by wired communication The step of controlling whether or not to acquire device information via the communication unit, the step of acquiring device information of the connected device, and the validity of the data receiving device are verified based on the acquired device information If it is verified that the data receiving device is valid in the step, the wireless communication unit transmits image information encrypted by the first encryption method. Comprising the steps of: controlling whether or not to transmit by the wired communication unit image information encrypted by the encryption method, the data transmission method is provided.

  In order to solve the above problem, according to another aspect of the present invention, a step of decoding image information of content received from a data transmission device by a first decoding method, and a content received from the data transmission device The device information of a device connected via a wireless communication unit that receives the image information of the content by wireless communication and the step of decoding the image information of the content by the second decoding method, or the content image by wired communication A step of controlling whether or not to acquire device information via a wired communication unit that receives information; a step of acquiring information of the connected device; and a connected device based on the acquired device information And verifying that the connected device is valid and receiving it by the wireless communication unit when it is verified that the connected device is valid. Comprising the steps of controlling whether or not to decode the second decoding scheme received by either wire communication unit is decoded, the data reception method is provided.

  In order to solve the above problem, according to another aspect of the present invention, a step of decoding image information of content received from a data transmission device by a first decoding method, and a content received from the data transmission device The image information of the data receiving apparatus through the second decoding method and the wireless communication unit that receives the image information of the content by wireless communication, or the image information of the content by wired communication A step of controlling whether or not to transmit device information via a wired communication unit that receives the data, a step of transmitting device information, and a data receiving device verified by the data transmitting device based on the transmitted device information The wireless communication unit performs the steps of acquiring the verification result of the validity of the data and the verification result that the data receiving device is valid. A step of controlling whether information is received and decoded by the first decoding unit or image information is received by the wired communication unit and decoded by the second decoding unit; and the first decoding unit or the second decoding Generating a display screen including the image information decoded by the converting unit. A data receiving method is provided.

  As described above, according to the present invention, it is possible to perform encryption by wireless communication and verify the validity of a device.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, the duplicate description is abbreviate | omitted by attaching | subjecting the same code | symbol.

First, an outline of a data transmission / reception system according to an embodiment of the present invention will be described. FIGS. 1A and 1B are explanatory diagrams showing configuration examples of the data transmission / reception systems 1 and 2 according to the present embodiment. As shown in FIG. 1A, the data transmission / reception system 1 includes a source device 400 such as a recording / reproducing device, a data transmission device 100, a data reception device 200, a sink device 300 such as a display, and the like. Is done. As shown in FIG. 1B, the data transmission / reception system 2 includes a source device 400 such as a recording / reproducing device, a data transmission device 100, and a sink device (also receiving data) 500 such as a display. Consists of.

The source device 400 is a device that records and reproduces content such as a TV program and a movie, and is a high-bandwidth HDCP (High-bandwidth).
It has a function of outputting content data from the output device of the source device 400 by using a content protection method such as Digital Content Protection System). Here, the source device 400 and the data transmission device 100 are, for example, HDMI (High-Definition).
The content data is transmitted by a transmission method such as TMDS ( Transition Minimized Differential Signaling) corresponding to an interface standard such as Multimedia Interface.

  In the data transmission / reception system 1, the data transmission device 100 is connected to the data reception device 200 by wireless communication, and encrypted content data is transmitted from the data transmission device 100 to the data reception device 200. Then, the content data received by the data receiving device 200 is displayed on a sink device 300 such as a television display connected by wire.

Similarly, in the data transmission / reception system 2, content data is output from the source device 400 via the data reception device 200. The data transmission device 100 and the sink device 500 that also receives data are connected by wireless communication. The encrypted content data is transmitted from the data transmission device 100, and the content data is received by the sink device 500. Is displayed on the display.

As described above, the source device 400 and the data transmission device 100 transmit content data using a content protection method such as HDCP. The HDCP standard prescribes device authentication on the transmission side and reception side, a key sharing method for authentication, an encryption method for transmitted content, and the like. Further, in the HDCP standard authentication, a device key for individually authenticating a communication partner apparatus by public key cryptography is used. When the authentication is successful between the transmission device and the reception device, the transmission device encrypts and transmits the video signal using the device key, and the reception device decrypts the received video signal using the device key.

  Further, in the HDCP standard, the above authentication processing is performed, and so-called Revocation processing (hereinafter referred to as revocation processing) for determining whether the receiving device is an unauthorized device is performed. Only after the revocation process determines that the receiving apparatus is not an unauthorized device, encrypted transmission is possible.

  In FIG. 1A, not only between the source device 400 and the data transmission device 100 but also when the data reception device 200 and the sink device 300 are securely connected using HDMI or the like, they are stored in each device. It is possible to determine whether or not the devices are legitimate devices by using the security information. Thereby, it becomes possible to permit signal transmission between different transmission / reception devices.

However, as shown in FIG. 1B, when the data receiving device is embedded in a display or the like and security information such as HDCP of the sink device 500 cannot be used, it is paired with a specific data transmitting device. If not used, unauthorized copying could not be prevented , and usability was poor. In wireless communication, image data is compressed according to image signals by DCT / Wavelet conversion or the like, and image data is transmitted at a reduced transfer rate. Therefore, when the content data is encrypted by HDCP, the content data must be encrypted again in order to transmit the image data by wireless communication after decrypting the content data.

Normally, the sink device 500 such as a display is provided with a wired input in addition to a wireless input. Therefore, in the present embodiment, it is authenticated that the data transmission device 100 and the sink device 500 are legitimate devices using security information provided for wired input. By using wired input security information, it becomes possible to perform HDCP revocation processing even in wireless communication. As a result, it is possible to verify the validity of a device by HDCP even in wireless communication, so even if HDCP security information is not stored on the receiving side, the copyright between the device and a device other than a specific transmission device is obtained. Content data can be transmitted and received.

  The outline of the data transmission / reception systems 1 and 2 has been described above. First, the data transmission / reception system 2 will be described. First, the functional configuration of the data transmission / reception system 2 will be described with reference to FIG.

FIG. 2 is a block diagram illustrating a functional configuration of a data reception portion of the data transmission device 100 and the sink device 500 that also performs data reception. In the present embodiment, the data transmission device 100 and the sink device 500 can be connected by wireless communication or wired communication. Further, the image information of the content is input to the data transmission device 100 . Image information is input to the sink device 500.

As illustrated in FIG. 2, the data transmission device 100 includes a switching unit 102, a control unit 104, a first encryption unit 106, a second encryption unit 108, an HDCP authentication processing unit 110, a device information acquisition unit 112, a verification unit. 114, a storage unit 116, a wireless communication unit 118, a wired communication unit 120, a switching unit 122, and the like. The sink device 500 includes a switching unit 502, a control unit 504, a first encryption unit 506, a second encryption unit 508, an HDCP authentication processing unit 510, a device information acquisition unit 512, a verification unit 514, a storage unit 516, and a wireless communication unit. 518, a wired communication unit 520, a switching unit 522, and the like.

Here, before describing details of the functional configurations of the data transmission device 100 and the sink device 500, the authentication processing and revocation processing in the HDCP standard will be described with reference to FIG. As shown in FIG. 3, the TX 10 that is a device that transmits content data and the RX 20 that is a device that receives content data are HDMI-connected. In a normal HDMI connection, there are a TMDS signal path for transmitting an image signal and a DDC signal path for transmitting HDCP authentication information and the like.

The TX10 and RX 20 that are HDMI-connected perform authentication processing according to the HDCP standard. That is, in the HDCP standard, copyright protection of content data is realized by performing the following processes (1) to (3).
(1) Authentication and shared key sharing between TX 10 and RX 20 (2) Content data encryption / decryption using shared key (3) Revocation processing by KSV

In the above (1), TX10 and RX 20 are mutually authenticated using a secret key given in advance to TX10 and RX20, and a shared key necessary for encrypting data is assigned to TX10. And RX 20 . The shared key is shared only between directly connected devices during the authentication process according to the HDCP standard.

In the above (2), decrypts the data using the shared key TX10 encrypts and transmits through the TMDS data, RX 20 uses the shared key shared in the processing of (1).

In (3) above, a so-called revocation process is performed in HDCP to determine whether RX 20 is an unauthorized device using a KSV (Key Selection Vector) that is uniquely determined according to the secret key of each device. Specifically, the RX 20 transmits its own KSV to the TX 10, and the TX 10 acquires a list of KSVs of unauthorized devices from the source device or the like. Then, the TX 10 verifies whether or not the KSV of the RX 20 is included in the acquired KSV list. If the KSV list includes the KSV of the RX 10, the RX 20 is regarded as an unauthorized device and the content data is not transmitted to the RX 20 .

  Therefore, transmission of content data by TMDS 11 from TX 10 to RX 20 shown in FIG. 3 is performed after successful authentication processing including revocation processing by HDCP. As a result, it is possible to prevent the content data from being transmitted to an unauthorized device, so that the copyright of the content data can be protected. The authentication process and revocation process in the HDCP standard have been described above.

  Next, a case where content data is transmitted and received by wireless communication will be described with reference to FIG. When content data is transmitted / received by wireless communication, content data is transmitted / received via a wireless TX 15 that transmits data by wireless communication and a wireless RX 25 that receives data by wireless communication. The radio TX 15 and the radio RX 25 are normally modulated with the same encryption strength as that applied to the TMDS signal. Also, when transmitting image information or the like by wireless communication, image data is compressed according to an image signal by a method using DCT / Wavelet conversion or the like, and the transfer rate is reduced. Therefore, when the content data is encrypted by HDCP, the content data must be encrypted again in order to transmit the image data by wireless communication after decrypting the content data, which complicates the processing.

  On the other hand, in the HDCP standard, when the encryption strength equivalent to that of the TMDS signal path is secured, it is not necessary to transmit the TMDS signal path. Therefore, when transmitting / receiving content data by wireless communication, the above-described complicated encryption / decryption processing is not performed if data is transmitted / received by the wireless TX 15 and the wireless RX 25 without transmitting / receiving the data by the TMDS 11 and TMDS 21. It will be good.

  However, even if the encryption strength equivalent to that of the TMDS signal path is ensured by wireless communication, the content cannot be protected unless the revocation processing by HDCP is performed. If the revocation process is not performed, the content data is transmitted even if the wireless RX 25 is an unauthorized device that is not permitted to receive the content data. Therefore, as to whether or not the device is an unauthorized device, content can be protected even in wireless communication by using revocation processing by HDCP.

  For example, when the wireless RX 25 is embedded in a display or the like and security information such as HDCP is not stored in the wireless RX 25, the above revocation processing cannot be performed and the pair is always used with a specific TX 15 Otherwise, the content could not be protected from unauthorized copying. However, if revocation processing is performed using security information stored in a display or the like, revocation processing can be performed using encryption by wireless communication. Thereby, even in wireless communication, it is possible to authenticate devices and arbitrarily combine a transmitting device and a receiving device. The case where content data is transmitted and received by wireless communication has been described above.

  Returning to FIG. 2, the first encryption unit 106 has a function of encrypting the image information of the input content by the first encryption method. The first encryption method is an encryption method used when content data (image information) is transmitted by wireless communication, and has the same encryption strength as that of the above TMDS. Further, the first encryption unit 106 may compress the image information according to the input image information of the content and then encrypt the image information using the first encryption method. For compression of image information, for example, a method using DCT / Wavelet conversion (time frequency component conversion) or the like can be used.

  The second encryption unit 108 has a function of encrypting the image information of the input content using the second encryption method. The second encryption method is encryption according to the HDCP standard, specifically, encryption using a shared key shared only between devices directly connected in the course of authentication processing. Further, the second encryption unit 108 may perform TMDS conversion on the image information of the encrypted content. Further, the second encryption unit 108 may be synchronized with the authentication process by the HDCP authentication processing unit 110. Specifically, after the authentication by the HDCP authentication processing unit 110 is successful, encryption is performed by the second encryption method.

  The wireless communication unit 118 is a communication interface such as a wireless LAN (Local Area Network) compatible communication device or a wireless USB compatible communication device. The wireless communication unit 118 has a function of transmitting the image information encrypted by the first encryption unit 106 by wireless communication.

  The wired communication unit 120 is a communication interface such as a wire communication device that performs wired communication, and can be exemplified by a wired connection unit that supports the HDMI standard. The wired communication unit 120 has a function of transmitting the image information encrypted by the second encryption unit by wired communication.

The HDCP authentication processing unit 110 performs device authentication according to the HDCP standard described above. The HDCP authentication processing unit 110 includes a device information acquisition unit 112, a verification unit 114, and the like. The device information acquisition unit 112 has a function of acquiring device information connected to the data transmission device 100. The device information is a KSV that is uniquely determined according to the secret key of each device as described above. The KSV is acquired from the sink device 500 including a data receiving device that transmits image information or a device connected to the sink device 500 .

The source device 400 has a function of verifying the legitimacy of the sink device 500 including the data receiving device and the device connected thereto based on the device information acquired by the data transmitting device 100. Specifically, verifies the validity of such a sink device 500 having a data receiver according to whether KSV, such as the sink device 500 having a data receiving apparatus KSV list of rogue devices described above are included . Whether output is possible is determined based on the result.

The control unit 104 controls switching of the switching unit 102 or the switching unit 122 to control whether data is transmitted / received using the wireless communication unit 118 or whether data is transmitted / received using the wired communication unit 120. Has the function of Specifically, when the switching unit 122 is switched to perform wireless communication with the sink device 500 including the data receiving device, the device information acquired by the device information acquisition unit 112 is acquired via the wireless communication unit 118. . When performing wired communication with the sink device 500 including the data receiving device, the switching unit 122 is switched so as to acquire device information via the wired communication unit 120.

When the verifying unit 114 verifies that the sink device 500 including the data receiving device is a valid device, the switching unit 122 is switched and encrypted via the wireless communication unit 118 or the wired communication unit 120. The received image information is transmitted to the sink device 500 provided with the data receiving device. In addition, when the switching of the switching unit 102 is controlled and wireless communication is performed with the sink device 500 including the data receiving device , the first encryption unit 106 encrypts the image information and the sink device 500 including the data receiving device. In the case of wired communication, the image information may be encrypted by the second encryption unit 108.

  The storage unit 116 may be a non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read-Only Memory) or an EPROM (Erasable Programmable Read Only Memory), for example. The storage unit 116 can store the KSV of the data receiving device 200a acquired by the HDCP authentication processing unit 110, the KSV list of unauthorized devices, and the like.

The functional configuration of the data transmission device 100 has been described above. Next, a functional configuration of the sink device 500 including the data receiving device will be described. Wireless communication unit 5 18, for example, a wireless LAN compatible communication apparatus, wireless USB compatible communication device is a communication interface such. Wireless communication unit 5 18 has a function of receiving the image information of the content transmitted by radio communication from the data transmitting apparatus 100.

The wired communication unit 5 20, for example, a communication interface, such as a wired communication device that performs communication by wire, can be exemplified such as a wired connection unit that corresponds to the HDMI standard. The wired communication unit 5 20 has a function of receiving the image information of the content transmitted by the wired communication from the data transmitting apparatus 100.

The first encryption unit 5 06 has a function of encrypting the first encryption method the image information of the received content by the wireless communication unit 5 18. The first encryption method is an encryption method used when content data (image information) is transmitted by wireless communication, and has the same encryption strength as that of the above TMDS. The first encryption unit 5 06, in accordance with image information of the input content may be encrypted by a first encryption scheme After compressing the image information. For compression of image information, for example, DCT / Wavelet conversion (time-frequency component conversion) can be used.

The second encryption unit 5 08 has a function of encrypting the image information of the received content by the wired communication unit 5 20 second encryption method. The second encryption method is encryption according to the HDCP standard, specifically, encryption using a shared key shared only between devices directly connected in the course of authentication processing. The second encryption unit 5 08, the image information of the encrypted content may be TMDS conversion. Further, the second encryption unit 5 08 may be synchronized with the authentication process by the HDCP authentication processing unit 5 10. Specifically, encrypted by the second encryption scheme after the HDCP authentication authentication processing unit 5 10 has succeeded.

HDCP authentication processing unit 5 10 performs an authentication and revocation processing apparatus according to the HDCP standard described above. HDCP authentication processing unit 5 10 has a function of acquiring the device information is connected to the sink device 500. The device information is a KSV that is uniquely determined according to the secret key of each device as described above. KSV is information acquired from a sink device or the like that transmits image information.

The control unit 5 04 controls the switching of the switching unit 5 02 or switching unit 5 22, or for transmitting and receiving data over a wireless communication unit 5 18, for transmitting and receiving data over a wired communication unit 5 20 It has a function to control whether or not. Specifically, by switching the switching unit 5 22, in the case of wireless communication and data transmission device 100, the device information acquired by the device information acquiring part 5 12 acquires via the wireless communication unit 5 18. Also in the case of wired communications and data transmission apparatus 100 switches the switching unit 5 22 to acquire the device information through the wired communication unit 5 20.

Next, a data transmission / reception method in the data transmission / reception system 2 will be described with reference to FIGS. FIG. 5 is a flowchart showing a data transmission / reception method in the data transmission / reception system 2 . As shown in FIG. 5, in the data transmission / reception method in the data transmission / reception system 2, an authentication process (S200) by HDCP is performed after a connection process (S100) by wireless communication is performed. After the HDCP authentication process (S200), the image information transmission process (S300) is performed. Next, details of each processing of wireless connection processing (S100), HDCP authentication processing (S200), and image information transmission processing (S300) will be described.

  First, connection processing by wireless communication in the data transmission / reception system 2 will be described with reference to FIG. FIG. 6 is a timing chart showing connection processing by wireless communication in the data transmission / reception system 2. As illustrated in FIG. 6, connection processing by wireless communication is performed between the data transmission device 100 and the sink device 500 including the data reception device. First, the sink device 500 provided with the data receiving apparatus notifies the data transmitting apparatus 100 to start connection by wireless communication (S102). In step S102, the data transmitting apparatus 100 notified of the connection start from the data receiving apparatus 200 responds (ACKs) to the connection start (S104).

  In step S104, the sink device 500 including the data receiving device that has received the response to the connection start from the data transmitting device 100 transmits the authentication information of the sink device 500 including the data receiving device (S106). In step S106, the data transmitting apparatus 100 that has received the authentication information from the sink device 500 including the data receiving apparatus transmits the authentication information of the data transmitting apparatus 100 (S108). The authentication information of each device transmitted and received in step S106 and step S108 is, for example, information calculated based on the identification information of each device or the identification information of each device.

  Then, based on the authentication information of each device in step S106 and step S108, authentication between the data transmitting device 100 and the sink device 500 including the data receiving device is performed (S110). The connection process by wireless communication in the data transmission / reception system 2 has been described above. If authentication is successful between the data transmission device 100 and the sink device 500 including the data reception device in step S110, an HDCP authentication process (S200) is performed. The connection process by wireless communication in the data transmission / reception system 2 has been described above.

  Next, an authentication process by HDCP in the data transmission / reception system 2 will be described with reference to FIG. FIG. 7 is a timing chart showing authentication processing by HDCP in the data transmission / reception system 2. As shown in FIG. 7, the source device 400 notifies the reception side of the data transmission device 100 of the start of authentication by HDCP (S202). Before the start of authentication is notified in step S202, a HotPlugDetect request is transmitted from the sink device 500 to the source device 400 via the data receiving apparatus 100. In step S202, HDCP authentication start notification is received from the source device 400. The source device 400 acquires authentication information and KSV (S204).

  Then, the receiving side of the data receiving apparatus 200 makes a subsequent HDCP authentication request to the data transmitting apparatus 100 (S206). In step S206, the transmission side of the data transmission device 100 that has received an authentication request from the reception side of the data transmission device 100 notifies the sink device 500 of the start of authentication by HDCP (S210). In step S210, the sink device 500 notified of the start of authentication from the data receiving apparatus 200 acquires the authentication information and KSV of the sink device 500 (S212).

Then, the transmission side of the data transmission device 100 transmits the KSV to the reception side of the data transmission device 100 (S214). Then, the source device 400 acquires a KSV list on the transmission side of the data transmission device 100 (S216). As described above, the KSV list is an unauthorized device KSV list. Then, the source device 400 collates the KSV list (S218).

  The authentication process using HDCP in the data transmission / reception system 2 has been described above. In step S218, when the source device 400 determines that the transmission destination for transmitting the image information of the content is a valid device, an image information transmission process (S300) is performed.

  Next, an image information transmission process in the data transmission / reception system 2 will be described with reference to FIG. FIG. 8 is a timing chart showing image information transmission processing in the data transmission / reception system 2. As shown in FIG. 8, the source device 400 transmits the encrypted image information to the reception side of the data transmission device 100 determined to be a legitimate device in step S218 (S302). The reception side of the data transmission apparatus 100 to which image information is transmitted from the source device 400 in step S302 performs image information conversion such as DCT / Wavelet conversion (S304). Then, the image information converted in step S304 is encrypted for transmission by wireless communication (S306). The image information encrypted in step S306 is transmitted to the transmission side of the data transmission apparatus 100 (S308).

In step S308, the transmission side of the data transmission apparatus 100 to which image information has been transmitted from the reception side of the data transmission apparatus 100 performs image information conversion such as DCT / Wavelet conversion (S310). Then, the image information converted in step S310 is encrypted for transmission by wireless communication (S312). The image information encrypted in step S306 is transmitted to the sink device 500 (S314). When the data transmission device 100 and the sink device 500 are connected by wire, the image information transmitted in step S308 is encrypted according to the HDCP standard and then subjected to TDMS conversion. Thereafter, the signal is transmitted to the sink device through the TDMS signal path. The image information transmission process in the data transmission / reception system 2 has been described above.

  The data transmission / reception system 2 according to the first embodiment has been described above. According to the data transmission / reception system 2, the image information of the content output from the source device 400 confirms the validity of the sink device 500 by HDCP revocation processing when connecting to the sink device 500 by wireless communication. Thus, the image information of the content is encrypted for transmission by wireless communication, and transmitted to the sink device 500 connected wirelessly.

In the present embodiment, since the wired output to the data transmission device 100 is provided, it is possible even with the data receiving device connected by wireless communication performing revocation processing HDCP. Similarly, since the sink device 500 is also provided with a wired input, the HDCP revocation process can be performed on the sink device 500 as well. Thereby, even in wireless communication, authentication between devices can be performed, and a transmitting device and a receiving device can be arbitrarily combined. That is, even when HDCP security information is not stored in the receiving device or the sink device, content data can be transmitted / received while protecting the copyright with a device other than the specific transmitting device.

(Second Embodiment)
In the second embodiment, the data transmission / reception system 1 shown in FIG. In the data transmission / reception system 1, the data transmission device 100 and the data reception device 200 can be connected by wireless communication or wired communication. Further, the data transmitting apparatus 100 is connected to the source device 400 by wire, and image information of content is input. The data receiving device 200a is wirelessly or wired connected to the sink device 300, and image information of content is input from the data receiving device 200 to the sink device 300.

  Also in this embodiment, since the revocation determination is made in the source device 400, the KSVs of the data receiving device 200 and the sink device 300 connected to the data transmitting device 100 via the data transmitting device 100 are transferred to the source device 400. Sent.

As shown in FIG. 9, the data transmission device 100 includes a switching unit 102, a control unit 104, a first encryption unit 106, a second encryption unit 108, an HDCP authentication processing unit 110, a wireless communication unit 118, a wired communication unit. 120, a switching unit 122, and the like. The data receiving apparatus 200 includes a switching unit 202, a control unit 204, a first encryption unit 206, a second encryption unit 208, an HDCP authentication processing unit 210, a device information acquisition unit 212, a verification unit 214, a wireless communication unit 218, a wired communication unit A communication unit 220, a switching unit 222, and the like are provided.

  The first encryption unit 106 has a function of encrypting image information of input content using a first encryption method. The first encryption method is an encryption method used when content data (image information) is transmitted by wireless communication, and has the same encryption strength as that of the above TMDS. Further, the first encryption unit 106 may compress the image information according to the input image information of the content and then encrypt the image information using the first encryption method. For compression of image information, for example, DCT / Wavelet conversion (time-frequency component conversion) can be used.

  The second encryption unit 108 has a function of encrypting the image information of the input content using the second encryption method. The second encryption method is encryption according to the HDCP standard, specifically, encryption using a shared key shared only between devices directly connected in the course of authentication processing. Further, the second encryption unit 108 may perform TMDS conversion on the image information of the encrypted content. Further, the second encryption unit 108 may be synchronized with the authentication process by the HDCP authentication processing unit 110. Specifically, after the authentication by the HDCP authentication processing unit 110 is successful, encryption is performed by the second encryption method.

  The wireless communication unit 118 is a communication interface such as a wireless LAN compatible communication device or a wireless USB compatible communication device. The wireless communication unit 118 has a function of transmitting the image information encrypted by the first encryption unit 106 by wireless communication.

  The wired communication unit 120 is a communication interface such as a wire communication device that performs wired communication, and can be exemplified by a wired connection unit that supports the HDMI standard. The wired communication unit 120 has a function of transmitting the image information encrypted by the second encryption unit by wired communication.

  The HDCP authentication processing unit 110 has a function of acquiring device information connected to the data receiving device 200. The device information is a KSV that is uniquely determined according to the secret key of each device as described above. KSV is information acquired from a sink device or the like that transmits image information.

  The control unit 104 controls switching of the switching unit 102 or the switching unit 122 to control whether data is transmitted / received using the wireless communication unit 118 or whether data is transmitted / received using the wired communication unit 120. It has the function to do. Specifically, when the switching unit 122 is switched to perform wireless communication with the data reception device 200, the device information acquired by the device information acquisition unit 112 is acquired via the wireless communication unit 118. When performing wired communication with the data receiving device 200, the switching unit 122 is switched so as to acquire device information via the wired communication unit 120.

The functional configuration of the data transmission device 100 has been described above. Next, the functional configuration of the data receiving apparatus 200 will be described. The wireless communication unit 218 is a communication interface such as a wireless LAN compatible communication device or a wireless USB compatible communication device. The wireless communication unit 218 has a function of receiving content image information transmitted from the data transmission device 100 by wireless communication.

The wired communication unit 220 is, for example, a communication interface such as a wire communication device that performs wired communication, and can be exemplified by a wired connection unit that supports the HDMI standard. The wired communication unit 220 has a function of receiving image information of content transmitted from the data transmission device 100 by wired communication.

  The first encryption unit 206 has a function of encrypting the image information of the content received by the wireless communication unit 218 using the first encryption method. The first encryption method is an encryption method used when content data (image information) is transmitted by wireless communication, and has the same encryption strength as that of the above TMDS. Further, the first encryption unit 206 may compress the image information according to the input image information of the content and then encrypt the image information using the first encryption method. For compression of image information, for example, DCT / Wavelet conversion (time-frequency component conversion) can be used.

  The second encryption unit 208 has a function of encrypting the image information of the content received by the wired communication unit 220 using the second encryption method. The second encryption method is encryption according to the HDCP standard, specifically, encryption using a shared key shared only between devices directly connected in the course of authentication processing. Further, the second encryption unit 208 may perform TMDS conversion on the image information of the encrypted content. Further, the second encryption unit 208 may be synchronized with the authentication process by the HDCP authentication processing unit 210. Specifically, after the authentication by the HDCP authentication processing unit 210 is successful, encryption is performed by the second encryption method.

  The HDCP authentication processing unit 210 performs device authentication according to the HDCP standard described above. The HDCP authentication processing unit 210 has a function of acquiring device information connected to the data receiving device 200. The device information is a KSV that is uniquely determined according to the secret key of each device as described above. KSV is information acquired from a sink device or the like that transmits image information.

The control unit 204 controls switching of the switching unit 202 or the switching unit 222 to control whether to transmit / receive data using the wireless communication unit 218 or whether to transmit / receive data using the wired communication unit 220. Has the function of Specifically, when the switching unit 222 is switched to perform wireless communication with the data transmission device 100 , device information acquired by the device information acquisition unit 212 is acquired via the wireless communication unit 218. Further, when performing wired communication with the data transmission device 100 , the switching unit 222 is switched so as to acquire device information via the wired communication unit 220. The functional configuration of the data receiving device 200 has been described above.

  Regarding connection processing by wireless communication, authentication processing by HDCP, and image information transmission processing according to the second embodiment, connection processing by wireless communication according to the first embodiment (S100), authentication processing by HDCP (S200), and image information transmission processing. Since it is almost the same as (S300), detailed description is omitted.

In the second embodiment, authentication by wireless communication is executed on the transmission side of the data transmission device 100 and the reception side of the data reception device 200. Then, the HDCP authentication request in the subsequent stage is notified from the data transmission device 100 to the sink device 300 via the data reception device 200. Thereafter, the authentication information and KSV of the sink device 300 are transmitted to the data transmission device 100 via the data reception device 200. Data transmission device 100 to the source device 400 to obtain the KSV list. Then, the KSV list is collated in the source device 400.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  For example, in the above-described embodiment, the switching unit is provided to switch whether to encrypt using the first encryption method or whether to encrypt using the second encryption method, but the present invention is not limited to such an example. . For example, the encryption of either the first encryption method or the second encryption method may be performed to control the output of the image information of the encrypted content. Further, the signal output from the TMDS circuit and the signal output from the wireless transceiver may be controlled.

It is explanatory drawing explaining the outline | summary of the data transmission / reception system concerning embodiment of this invention. It is a block diagram which shows the function structure of the data transmitter concerning 1st Embodiment of this invention, and a data receiver. It is explanatory drawing explaining the authentication process and revocation process in the HDCP specification concerning the embodiment. It is explanatory drawing explaining the case where content data are transmitted / received by the radio | wireless communication concerning the embodiment. It is a flowchart which shows the data transmission / reception method concerning the embodiment. It is a timing chart which shows the connection process by the radio | wireless communication concerning the embodiment. 6 is a timing chart showing authentication processing by HDCP according to the embodiment. It is a timing chart which shows the image information transmission process concerning the embodiment. It is a block diagram which shows the function structure of the data transmitter concerning the 2nd Embodiment of this invention, and a data receiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Data transmitter 200 Data receiver 102,122,202,222 Switching part 104,204 Control part 106,206 1st encryption part 108,208 2nd encryption part 112,212 Equipment information acquisition part 114,214 Verification part 118, 218 Wireless communication unit 120, 220 Wired communication unit 300 Sink device 400 Source device 500 Sink device provided with data transmission device

Claims (16)

A first encryption unit that encrypts image information of the input content using a first encryption method;
A wireless communication unit for transmitting the image information encrypted by the first encryption unit by wireless communication;
A second encryption unit for encrypting image information of the input content by a second encryption method;
A wired communication unit that transmits the image information encrypted by the second encryption unit by wired communication;
And the device information acquisition unit that acquires device information of the connected equipment,
Based on the device information acquired by the device information acquisition unit, an authentication unit that authenticates the validity of the data receiving device;
When the device information is acquired via the wireless communication unit and the data reception device is authenticated by the authentication unit, the image information encrypted by the first encryption unit is transmitted to the wireless communication unit. Send by
When the device information is acquired through the wired communication unit and the data receiving device is authenticated by the authentication unit, the image information encrypted by the second encryption unit is transmitted to the wired communication unit. A control unit that controls transmission by the unit;
A data transmission device comprising: The data transmission device according to claim 1, wherein the control unit controls the image information to be transmitted by either the wireless communication unit or the wired communication unit .   The data transmission device according to claim 1 or 2, wherein the control unit notifies the data reception device of start of authentication according to the HDCP standard. The device information acquisition unit acquires information on unauthorized devices from an external device,
The authentication unit determines that the data receiving device is a valid device when the device information of the data receiving device is not included in the information on the unauthorized device acquired by the device information acquiring unit. Item 4. The data transmission device according to any one of Items 1 to 3 . Wherein the first encryption unit encrypts the first encryption scheme After compressing the image information in accordance with image information of the content, the data transmission device according to any one of claims 1-4. A wireless communication unit for receiving image information of content from a connected data transmission device by wireless communication;
A first decoding unit for decoding the received image information of the content by a first decoding method;
A wired communication unit that receives image information of content from a connected data transmission device by wired communication;
A second decoding unit for decoding the received image information of the content by a second decoding method;
And the device information acquisition unit that acquires device information of the connected equipment,
Based on the device information acquired by the device information acquisition unit, an authentication unit that authenticates the validity of the connected device;
When the device information is acquired via the wireless communication unit and the connected device is authenticated by the authentication unit, the image information is received by the wireless communication unit and the first information is received. Decoding the image information by a decoding unit,
When the device information is acquired via the wired communication unit and the connected device is authenticated by the authentication unit, the image information is received by the wired communication unit and the second information is received. A control unit that controls the decoding unit to decode the image information ;
A data receiving device. The data receiving apparatus according to claim 6 , wherein the control unit controls the image information to be transmitted by either the wireless communication unit or the wired communication unit .   The data transmission device according to claim 6 or 7, wherein the control unit notifies the connected device of the start of authentication according to the HDCP standard. The device information acquisition unit acquires information on unauthorized devices from an external device,
The authentication unit determines that the connected device is a legitimate device when the information on the unauthorized device acquired by the device information acquisition unit does not include the information on the connected device. The data receiving device according to any one of claims 6 to 8 . The data receiving device according to claim 6 , wherein the first decoding unit compresses the image information according to the image information of the content and then decodes the image information using the first decoding method. A wireless communication unit for receiving content image information by wireless communication with a connected data transmission device;
A first decoding unit for decoding the received image information of the content by a first decoding method;
A wired communication unit for receiving content image information by wired communication with a connected data transmission device;
A second decoding unit for decoding the received image information of the content by a second decoding method;
A device information transmitter for transmitting device information of the data receiving device;
The authenticated by the data transmission device based on the device information transmitted by the device information transmitting unit, an authentication result acquisition unit that acquires the authentication result of the validity of the data receiving device,
When the device information is transmitted via the wireless communication unit, and the authentication result acquisition unit acquires an authentication result that the data reception device is valid, the wireless communication unit receives the image information and Decrypted by the first decryption unit;
When the device information is transmitted via the wired communication unit and the authentication result acquisition unit acquires an authentication result indicating that the data reception device is valid, the wired communication unit receives the image information and A control unit that controls the second decoding unit to perform decoding ;
A display screen generation unit that generates a display screen including the image information decoded by the first decoding unit or the second decoding unit;
A data receiving device. The display screen generation unit is provided in a display device incorporated in the data receiving device,
The device information transmission unit transmits device information of the display device,
The data reception device according to claim 11 , wherein the verification result acquisition unit acquires a verification result of validity of the data reception device verified by a data transmission device based on device information of the display device. The data receiving device according to claim 11 , wherein the first decoding method is a decoding method used when image information of content is transmitted by wireless communication. Encrypting image information of input content by a first encryption method;
Encrypting image information of input content by a second encryption method;
Acquire device information of a connected device via a wireless communication unit that receives content image information by wireless communication, or acquire the device information via a wired communication unit that receives content image information by wired communication. Determining whether or not to acquire the device information of the connected device; and
Authenticating the validity of the data receiving device based on the acquired device information;
When the device information is acquired via the wireless communication unit and the data receiving device is authenticated by the authenticating step, the image information encrypted by the first encryption unit is wirelessly transmitted. A step of controlling the communication unit to transmit,
When the device information is acquired via the wired communication unit and the data receiving device is authenticated by the authenticating step, the image information encrypted by the second encryption unit is stored in the wired communication unit. A step of controlling the communication unit to transmit,
Including a data transmission method. Decrypting the image information of the content received from the data transmitting device by the first decoding method;
Decoding the image information of the content received from the data transmitting device by a second decoding method;
Device information of a device connected via a wireless communication unit that receives content image information by wireless communication is acquired, or device information is acquired via a wired communication unit that receives image information of content by wired communication. Controlling whether or not,
Obtaining information of the connected device;
Authenticating the legitimacy of the connected device based on the acquired device information;
When the device information is acquired via the wireless communication unit and the connected device is authenticated by the authentication unit, the image information is received by the wireless communication unit and the first information is received. Controlling to decode the image information by a decoding unit;
When the device information is acquired via the wired communication unit and the connected device is authenticated by the authentication unit, the image information is received by the wired communication unit and the second information is received. Controlling to decode the image information by a decoding unit;
Including a data receiving method. Decrypting the image information of the content received from the data transmitting device by the first decoding method;
Decoding the image information of the content received from the data transmitting device by a second decoding method;
Whether the device information of the data receiving device is transmitted via a wireless communication unit that receives image information of content by wireless communication, or the device information is transmitted via a wired communication unit that receives image information of content by wired communication Controlling whether or not,
Transmitting the device information;
Obtaining the authentication result of the legitimacy of the data receiving device authenticated by the data transmitting device based on the transmitted device information;
When the authentication information indicating that the data reception device is valid is acquired by the step of transmitting the device information via the wireless communication unit and acquiring the authentication result, the image information is received by the wireless communication unit. A step of controlling the first decoding unit to perform decoding,
When the authentication information indicating that the data receiving apparatus is valid is acquired by the step of transmitting the device information via the wired communication unit and acquiring the authentication result, the image information is received by the wired communication unit. A step of controlling the second decoding unit to perform decoding,
Generating a display screen including the image information decoded by the first decoding method or the second decoding method;
Including a data receiving method.

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